Mechanical reversing device for the wire guide on coil winding machines



May 30, 1961 o. WIRTH 2,986,041

MECHANICAL REVERSING DEVICE FOR THE WIRE GUIDE ON COIL WINDING MACHINES Filed Oct. 26, 1959 CLUTCHES IN VENTOR ATTORNEYS United States Patent 2,986,041 REVERSING DEVICE FOR THE WIRE GUIDE 0N COIL WINDING MACHINES one Wirth, Zurich, Switzerland, assignor to Micafil A.-G., Zurich, Switzerland, a joint stock company Filed Oct. 26, 1959, Ser. No. 848,821

Claims priority, application Switzerland Mar. 5, 1957 3 Claims. CI. 74-40 This invention relates in general to machines for winding. wire coils for electrical apparatus from very fine wire and more particularly to an improved arrangement for winding such coils which have a very small layer width. The present application is a continuation-in-part of my prior and; pending application Serial No. 718,343 filed February 28, 1958 and now abandoned.

Coil winding machines are provided with a wire guide which is arranged to have a traverse movement, back and forthalong the machine so as to guide and distribute the wire evenly in layers on the coil being wound. A reversing mechanism is associated with the wire guide so. as to reverse. the movement of the same each time the. guide completes the Winding of one layer, i.e. when reaching the end of one layer, so as to start back in the opposite direction with the winding of the next adjacent layer. This back and forth motion of the wire guide. continues until the desired number of layers have been wound onto the coil. Prior to the present invention it has not been possible to arranged for the necessary periodic reversal of the wire guide when it is desired to wind coils in which the width of the layer is very small. With previously known arrangements, the minimum travel of the wire guide before reversal of its direction of motion could take place has been of the order of from five to eight millimeters. Consequently, the minimum coil width heretofore possible has been of, this same order.

The object of the present invention is to provide an improved arrangement for controlling the lateral traverse of the wire guide of the coil winding machine and is characterized by a reversing bar actuatable in a reciprocable manner by a wire guide, the reversing bar serving to actuate a double pawl lever which in turn serves to control the release of a drive organization that effects the periodic reversal of the wire guide itself as the latter reaches the end of its traverse. The double pawl arrangement requires but a very small displacement in order to perform its function and hence makes it possible when desired to effect reversals of the wire guide when the latter has travelled only a very small distance of the order of one millimeter, or less. Consequently, the, present invention makes it possible to wind coils having a winding layer width down to one millimeter or less. Wider coils can also be wound by adjusting the amount of free travel of the wire guide relative to the reversing bar.

The foregoing aswell as other objects and advantages of the invention will become more apparent from the following detailed description of a preferred embodiment thereof when considered with the accompanying drawing, the view being generally a side elevation of the mechanisrn and with certain parts shown in central longitudinal section for a clearer understanding.

With reference now to the drawing, numeral 1 designates a double toed rocking pawl which is mounted on a pivot 2 located intermediate the ends thereof for a rocking: motion backand forth about the. pivot axis.

Patented May 30, 1961 Ice 2 Motin is imparted to the pawl by means of a rectilinearly movable reversing bar 3 which is pivotally connected to the pawl 1 at 4. The reversing bar 3 is mounted for its rectilinear movement back and forth, so as to rock the pawl 1 back and forth, in spaced bearing sleeves 5 and 6 provided on the winding machine. Located on the bar 3 between the bearing sleeves 5 and 6 are a pair of stops or collars 7, 8. These collars are secured to the bar 3 at the desired spacing therebetween by means of set screws 9. Located on the bar 3 between the stop collars 7, 8 is a part 10 of, and which is actuated by, and in the same direction as, the wire guide of the machine. For the sake of simplicity, the complete wire guide structure has not been illustrated. However, it will be understood that when the wire guide of the machine runs to the right as viewed in the drawing to wind one layer of the coil, the part 10 will also move to the right along the bar 3, and to the same extent, in the direction of the solid arrow. Similarly, when the wire guide runs to the left to wind the next adjacent layer of the coil, part 10 will move to the left on bar 3 as indicated by the dashed arrow and to the same extent. When moving to the right, the part 10 will move along bar 3 until it strikes the stop collar 7 thus picking up the bar 3 and also moving it to the right which then causes the pawl 1 to be rocked counterclockwise in the direction indicated by the solid arrow. When moving to the left, part 10 will move along bar 3 until it strikes the stop collar 8 thiis picking up bar 3 and also moving it to the left which then causes the pawl 1 to be rocked clockwise in the direction indicated by the dashed arrow.

It will be seen from the drawing that rocker pawl 1 is provided with a toe 1a at one end thereof and a similar toe 1b at the opposite end. Cooperative with the rocker pawl toes 1a and 1b is a latch pin 11 located at the end of a reversing lever 12 which is mounted on a rock shaft 13 for movement between an upper position shown in solid lines and a lower position shown in dashed lines Also mounted upon the rock shaft 13 is a rocking lever;14 which is provided with switching rods-15 and 15' which are pivotally secured to the end portions of lever 14 by means of pivotal connections 16. As rocking lever 14 is rocked clockwise, switching rod 15 is moved upwards and switching rod 15' is moved simultaneously downwards. When rocking lever 14 is rocked counterclockwise, switching rod 15 is moved downwards'andswitching rod 15 is moved simultaneously upwards. The directional movements of rods 15* and 1 5' are indicated by the solid and dashed arrows and these rodsservet'o eife'ct reversal of the direction of motion of the wire guide on the machine by means of suitable reversing clutches which may be actuated by mechanical, electrical, hydraulic or pneumatic means. To simplify illustration, these reversing clutches have been illustrated diagrammatically by rectangle 20, and the drive outputs therefrom to the wire guide member 10 for driving the latter to the; right and left respectively have likewise been illustrated diagrammatically by solid and dashed lines. Control of the operation of reversing clutches 20 by the switching levers 15, 15' has also been illustrated diagrammatically by the dash-dot lines.

The latch pin. 11 is received in a bore located at the end of the reversing lever 12 and is loaded by a helical spring 1 7 so as to, act-in a direction outwardly from the end of lever 12. Outward movement of the latch'pin 11 is limited by a head 11a thereon. As indicated in the drawing, latch pin 11 is engaged with either thetoe portion 1a or 1b of the rocker pawl 1. As rocker pawl is rocked counterclockwise the toe portion 1a releases;i t self from latch pin 11 and the latter, together with the reversing lever- '12, move downwardly, the end ofthe, latch pin 11 following 'a1ong-and--in contactwith 'the' curved surface of the rocker pawl 1. When the latch pin 11 and reversing lever 12 have nearly reached their lowermost position, latch pin 11 will have been pressed inwardly against the action of spring 17 due to its following along the curved surface 1c. Then when pin 11 clears the toe portion 11: at the lower end of pawl 1, spring 17 will cause the pin 11 to move outwardly and be locked behind toe 1b, thus holding the reversing lever 12 in the lowermost position as indicated by the dashed lines. Reversing lever 12 will remain in this lowermost position until pawl 1 is actuated once again, this time in a clockwise position, whereupon the toe 1b will be released from latch pin 11 thus to permit movement of reversing lever 12 upwards until it reaches its terminal position wherein the latch pin 11 is similarly locked behind the other toe portion In.

I The reversing lever 12 is actuated upwards and downwards by means of a drive bar 18 and connecting head 19 pivotally secured to lever 12 at 21. The connecting head 19 is threaded onto the threaded end of bar 18, and hence bar 18 may be threaded into or out of the head 19 thus to effectively shorten or lengthen, as the case may be, the length of bar 18 as regards its connection to reversing lever 12. The bar 18 and head 19 can be locked in the desired position of longitudinal adjustment by means of a counter or lock nut 22.

At the opposite threaded end of bar 18, a similar threaded head 23 and counter nut 24 are provided in order to permit a similar adjustment for the effective length of this end of bar 18. The head 23 includes a bore for mounting upon a crank pin 25 of a crankshaft 26, and is retained upon the crank pin 25 by means of a Seeger ring 27. The eccentricity of the arrangement, i.e. the distance E between the axis of rotation of crankshaft 26 and the axis of pin 25 corresponds to one-half the stroke H of reversing lever 12. The exact truing or adjustment of lever 12 in its relation to rocker pawl "1 is effected by means of the screw adjustments at the upper and lower bar heads 19 and 23.

The crankshaft 26 is mounted for rotation about a horizontal axis in a stationary bearing block 28 by means of ball bearings 29 which are retained against axial displacement in block 28 by means of Seeger rings 30, and are spaced from each other by means of spacer sleeves 31 which surround crankshaft 26.

A slipping clutch arrangement is used for driving the crankshaft 26 in rotation in order that a constant torque may be applied thereto. In particular, crankshaft 26 is provided with a flange 32 to which is secured a friction face plate or clutch disc 33 which may be made from a composition of asbestos material, the disc 33 being attached to the flange 32 by means of screws 34 or the like. A pulley 35 is rotatably mounted upon crankshaft 26 by means of a bearing bush 36, and rotation or torque of the revolving pulley 35 is applied directly to the facing of clutch plate 33 by means of a pressure disc 37 coupled to pulley 35 by means of a plurality of helical compression springs 38. Pressure disc 37 is likewise rotatably mounted upon crankshaft 26 by means of a bush 39, and the pressure exerted axially by disc 37 which is transmitted through springs 38 to pulley 35, and from the latter to the face of clutch plate 33 can be adjusted by means of a disc 40 mounted upon the end of crankshaft 26 and which is brought to bear with an adjustable degree of force against the end face of disc 37 by means of a nut 41 which is threaded onto the threaded end of crankshaft 26. A belt 42, which serves for the drive of the winding machine, has a fiat portion which runs in peripheral contact with pulley 35, and the latter is disposed between the pulley of the drive motor which furnishes the power and the drive pulley of the winding machine, these latter two pulleys not being illustrated. Consequently, pulley 35 is driven continuously by belt 42 so long as the winding machine is operating and hence imparts a constant torque to crankshaft 26 through the intermediary of the slippable clutch plate 33.

Operation When the reversing lever 12 is in the position indicated by full lines, the torque constantly applied to crankshaft 26 exerts a downward pull upon bar 18 but the latter cannot move downward until pawl 1 has been actuated to withdraw the toe 1a from latch pin 11. This takes place as soon as the wire guide member 10, which will then be moving to the right in the direction of the solid arrow, picks up the stop 7 which is secured to the reversing bar 3, and shifts the latter to the right, thus rocking the pawl 1 counterclockwise in the direction of the solid arrow. Reversing lever 12 is thereby released, permitting bar 18 to be pulled down to a position corresponding to a half revolution of crankshaft 26 and shifting lever 12 to the position shown in broken lines. This causes rocking lever 14 to be rotated counterclockwise to thus actuate switch rod 15 downwardly and switch rod 15' upwardly which serves to reverse the direction of movement of wire guide 10 and the latter will then begin to move to the left. As previously explained, the reversible drive mechanism on the machine including the reversing clutches 20 controlled by the switch rods 15, 15' which actually drives the wire guide, of which member 10 is a part, back and forth along the machine, has not been illustrated in structural detail since it is conventional on winding machines of this general type.

Movement of wire guide 10 to the left will then continue until it picks up the stop member 8 which then causes reversing bar 3 to shift to the left in the direction of the broken line arrow. This serves to actuate pawl 1 in the opposite direction thus releasing toe 1b from latch pin 11 and permitting the torque applied to crankshaft 26 to push bar 18 upward and rock lever 14 in the opposite direction which then causes rod 15 to move upwardly and rod 15' to move downwardly which again reverses the wire guide and starts its movement to the right.

The length of the stroke of the wire guide and its part 10 to the left and right is thus primarily determined by the distance between the stops 7 and 8. This will thus determine the width of the winding layer. When the stops 7 and 8 are set practically against the opposite faces of the wire guide part 10, then the latter will have substantially no initial free movement relative to the reversing bar 3 in which event reversal of the wire guide will take place each time the latter and reversing bar 3 together travel the relatively small distance required to effect the release of the pawl toes 1a, 1b from the latch pin 11. This distance can be made very small dependent upon the distance between the pivots 2 and 4, and it has proven practical to effect actuation of pawl 1 after a travel together of the part 10 and reversing bar 3 of only a distance of one millimeter or even less. Consequently, this means that the improved arrangement will permit coils to be wound having a layer width of one millimeter or less.

In conclusion, it will be understood that the present invention is not limited to the exact construction which has been described and illustrated but rather can be departed from in minor details without, however, departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. Apparatus for controlling the lateral traverse of a wire guide member of a coil winding machine comprising a rocker pawl pivotally mounted intermediate the ends thereof and being provided with a toe at each end thereof, a reversing bar connected to said rocker pawl for actuating the same, adjustable stops on said reversing bar, said wire guide member being movable back and forth along said reversing bar between said stops to effect engagement with one and then the other of said stops and thereby couple said wire guide member and reversing bar to effect a back and forth movement of said reversing bar and hence a rocking movement of said rocker pawl, a pivotally mounted reversing lever for controlling the direction of movement of said wire guide member, said reversing lever having the outer end thereof cooperative with the toes of said rocker pawl and being movable be tween and engageable by one and then the other of said toes, and means actuating said reversing lever back and forth between the toes of said rocker pawl whenever released by said toes as said rocker pawl is actuated, last said means including a drive bar pivotally connected at one end to said reversing lever, the other end of said drive bar being secured to a pin on a crankshaft and which pin is located eccentrically to the axis of rotation of said crankshaft, and means imparting a torque to said crankshaft.

2. Apparatus as defined in claim 1 wherein said means 6 for applying a torque to said crankshaft includes a slipping clutch, said crankshaft and pin being released for rotation in steps of one-half revolution each upon each movement of said rocker pawl.

3. Apparatus as defined in claim 1 wherein said reversing lever is provided with a spring-loaded latch pin which cooperates with the toes of said rocker pawl, said latch pin being slidable along the edge of said rocker pawl when released from one of said toes until it engages 10 behind the other toe.

References Cited in the file of this patent UNITED STATES PATENTS Tallon Sept. 17, 1912 2,259,291 Chapman Oct. 14, 1941 

